Unknown plant

[Lvandelft]

I am sure that somebody will know this plant. I saw it at Gardens Open day in our village and the owner
could not give a name.
It is about 60- 80 cm high and the stems are not roundish but quadratic. I presume some Verbenaceae or
Scrophulariaceae?

[Lvandelft]

I see that there many people had a look at this question but I got no answer to my question.
By accident some one who I know here, visited the same garden and he told the owner what the
plant is and today he told it to me too.
It should be Nepeta nuda, white form, probably Nepeta nuda ssp. albiflora.